<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
  <form action="calculate/sum" method="post">
    <h1>计算器</h1>
    数字1：<input name="num1" type="text"><br>
    数字2：<input name="num2" type="text"><br>
    <input type="submit" value=" 点击相加">
  </form>
</body>
</html>